I'm looking for a 7.3 IDI 5spd truck. the question is wether or not i should focus on a turbo model or not. is the performance and milage worth the search? they are harder to find. Would i find myself wishing for one later? would use as DD and occasional 7000lb towing duty. I dont want to spend thousands later , I'd help it breath a little better, maximize its tuning and call it good.

thanks, Vince

 

I bought mine without and was happy at sea level until I tried pulling approx 10K up hill at high elevation. It was sick. There are a lot of GOOD posts concerning getting it to breathe properly in lieu of turbo charging it

 

If you can find a IDI with a turbo, you'ld be ahead of the game but what happens if you stumble across a real gem with out a turbo? My point is...there's more to a to the these old trucks than a turbo. The money you save buying one with a turbo, you might be spending on a front end, tranny, IP, etc, etc...[stock 7.3 IDI Turbo is min. 12 years old] even the little things all add up. I hope you find what your looking for, lol.

 

I've been lurking on these forums for awhile now and have noticed there seems to be two theories on these IDI's. the turbo guys and the header (non-turbo) guys. I'm looking at mostly high mile rigs, 200-250K. is the turbo more of an issue at higher mileage? Ive heard of oil pressure issues. I think I want a turbo, and feel it would be cheaper in the long run to buy one already setup.

what are the pros and cons of the three- nonturbo, factory turbo, aftermarket turbo- is there a turbo setup I should avoid?

what signs should a diesel newbie be looking for when checking out a rig, good or bad?

I am seriously looking, but in no hurry. I hope to be well informed and have no regrets after I do buy. these forums are great and you guys are indespensible, I can only hope I can give somthing back in the future.

vince

 

bc6.9, I hear you. i'm pretty handy with chassis work and am comfortable at asessing them. its the motor i'm worried about.

 

Well, I can relate...10 years ago when I bought my 86, I didn't have a clue about diesels...all I knew [at that time] is that were expensive to fix. So I wanted an IDI that was in good shape. I have learnt a lot since then, mostly on this forum, so your way ahead of where I was when I bought my first diesel.

I have an 84 6.9 4x4 that I bought off a good friend of mine...he completely restored the truck, except the IDI...in fact in was in the process of installing a cummins, but that another story. I have done some work on the motor and have yet to install a turbo....the IDI has 300,000 klms on it. runs well, but puffs some blue. When do install a turbo, I know that the motor is long in the tooth and may not be able to with stand the extra stress [for long] that the turbo will inflict on it. I knew when I bought the truck that at some time in the future, I'd be replacing the motor, so what I guess I'm saying, the pros & cons of installing a turbo on an aging IDI vs installing headers is an educated point view....
-any real power, requires a turbo
-high compression IDI's are not ideal canidates for a turbo
-6.9 heads should have reinforced studs
-FTE members have reported turbos running boosts of 10 to 14lbs with no problems
-headers are a 1/5 the price of a new turbo
-headers do not pose any threat of damage to an IDI

This is just the tip of the ice berg, and the debates rages on.

 

thanks for the insight.

Do the N/A(naturally asperated?) IDI engines have the same compression ratio and head bolts as the factory turbo IDI?

 

No, 6.9 & 7.3 heads are different and am not quite sure of difference of compession of each, I belive

6.9 head bolts are 7/16
7.3 head bolts are 1/2
factory turbos only came on 7.3 IDI's with lower compression than non turbo 7.3
stock 7.3 turbo vs stock 7.3 non turbo was only 10 to 15 hp increase
mods can greatly increase hp's on the 7.3 turbo

 

6.9 was 22.5 to 1
7.3 was 21.5 to 1
7.3 turbo was 21.5 to 1
7.3 Power Stroke was 18 to 1

NA motors had 1 " wrist pins.
Some of the turbo 7.3 engines had 1n5/16" wrist pins.

 

What does the propane injection do for these rigs, is it a power or mileage thing? can a turbo motor use it?

 

thanks Dave, hey does NA stand for naturally aspirated? still learning the lingo.

I've surfed waaaay back in these forums and see you built a sweet engine this last year.

I've built a few nice gassers, but no diesels.

I appreciate all the info from you guys, its going to good use.

 

Both and yes....

 

thanks guys,

hey, does NA stand for naturally asperated? still learning the lingo.

I apreciate all the info from you guys, I'm gonna put it to good use.

 

Yup, right on the money...

 

No smoke grinders for me on my 6.9. I couldn't have just one just one. I would have to stage a couple, pour the fuel to it to justify 100 psi of boost then I would have to inject water. I would have to "crashbox" my T19........I do this stuff for people, I need to stay away from my own.

Dave would have to try to catch me

We would both loose. We would each have a melted down 6.9 and needing a ride home.


Marry Xmas